Clinical traits and systemic risks of familial diabetes mellitus according to age of onset and quantity: an analysis of data from the community-based KoGES cohort study.

Objectives: The aim of this study was to clarify the clinical trait of familial diabetes mellitus (DM) by analyzing participants' risk of DM according to the age of DM onset in parents and siblings, and to evaluate individuals' risk of DM-associated cardiometabolic diseases.

Methods: Altogether, 211,173 participants aged ≥40 years from the Korean Genome and Epidemiology Study were included in this study. The participants were divided into groups based on the number (1 or 2 relatives) and age of onset (no DM and early, common, or late onset) of familial DM. Participants' risk of DM was assessed using a Cox regression model with hazard ratios and 95% confidence intervals (CIs). A logistic regression model with odds ratios was used to evaluate associations among the participants' likelihood of acquiring cardiometabolic diseases such as hypertension, chronic kidney disease (CKD), and cardiovascular disease.

Results: The risk of developing DM was 2.02-fold (95% CI, 1.88 to 2.18) and 2.88-fold (95% CI, 2.50 to 3.33) higher, respectively, in participants with 1 and 2 family members diagnosed with familial DM. It was 2.72-fold (95% CI, 2.03 to 3.66) higher in those with early-onset familial DM. In the early-onset group, the respective risks of hypertension and CKD were 1.87-fold (95% CI, 1.37 to 2.55) and 4.31-fold (95% CI, 2.55 to 7.27) higher than in the control group.

Conclusions: The risk of DM and related cardiometabolic diseases was positively associated with the number of family members diagnosed with DM and an early diagnosis in family members with DM.